exp_fcn.h

Go to the documentation of this file.

/* SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright(c) 2022-2025 Intel Corporation.
 *
 * Author: Shriram Shastry <malladi.sastry@linux.intel.com>
 *         Seppo Ingalsuo <seppo.ingalsuo@linux.intel.com>
 *     Pasca, Bogdan <bogdan.pasca@intel.com>
 */
 
#ifndef __SOFM_EXP_FCN_H__
#define __SOFM_EXP_FCN_H__
 
#include <stdint.h>
 
#if defined(__XCC__)
/* HiFi */
#include <xtensa/config/core-isa.h>
#if XCHAL_HAVE_HIFI5 == 1
#define SOFM_EXPONENTIAL_HIFI5 1
#elif XCHAL_HAVE_HIFI4 == 1
#define SOFM_EXPONENTIAL_HIFI4 1
#elif XCHAL_HAVE_HIFI3 == 1
#define SOFM_EXPONENTIAL_HIFI3 1
#endif
#else
/* !XCC */
#define EXPONENTIAL_GENERIC 1
 
#endif
 
/* Q5.27 int32(round(log((2^31 - 1)/2^20) * 2^27)) */
#define SOFM_EXP_FIXED_INPUT_MAX    1023359037
 
/* Q8.24 int32(round((log((2^31 - 1)/2^20) * 20 / log(10)) * 2^24)) */
#define SOFM_DB2LIN_INPUT_MAX       1111097957

int32_t sofm_exp_approx(int32_t x);

int32_t sofm_exp_fixed(int32_t x);
 

int32_t sofm_db2lin_fixed(int32_t db);
 
#endif /* __SOFM_EXP_FCN_H__ */